Ordnance firing mechanism



Patented Nov. 23, 1920.

A. T. DAWSON AND G. T. BUCKHAM.

ORDNANGE FIRING MECHANISM.

APPLICATION FILED MAY 29. 1918.

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ARTHUR TREVOR DAVISON AND enonen THOMAS BUCKHAM, or wns'rmnvsrnn,

LONDON, ENGLAND, assienons 'ro vicxnus LIMITED, or WESTMINSTER,

ENGLAND.

GRDNANCE Frame MECHANISM.

Application filed May 29, 1918. Serial No. 237,363.

This invention relates to firing mechanism for ordnance of the kind havir a sliding lock frame movable transversely to the axis of the gun in a box slide attached to the rear end of the axial vent bolt.

According to the invention the lock frame carries a striker of the hammer'type pivoted to move in a plane transverseto thepath of travel of the lock frame, this arrangement enabling the hammer to be cocked by a lanyard without possibility of the lock frame being displaced from its closed position by the pull of the lanyard and obviating the necessity for a locking pin to prevent this movement; it also enables the overall length of the lock to be reduced to a minimum. Carried in the lock frame is the firing spring and plunger, the latter being preferably so arranged asto engage with projections disposed on the hammer one on each side of the hammer pivot; this'arrangement' gives a balancing effect to the hammer so as to cause it to be slightly withdrawn to a retracted position after firing, the momentum of the rapidly moving hammer when firing being more than sufiicient to overcome the slight initial spring pressure necessary for retraction. p 7

In order that the said invention may be clearly understood and readily carried into effect we will describe the same 'more fully with reference to the accompanying drawings in which v Figure 1 is a rear elevation showing the improved lock mechanism in position on the gun, the lock frame in this figure being adapted to move in a path at an angle to the vertical.

Fig. 2 is a rear elevation of the improved lock mechanism, the lock frame in this case being adapted to move in a vertical path.

Fig. 3 is a plan of Fig. 2.

Fig. it is a section taken approximately on the line L, l of Fig. 2.

Fig; 5' is a view'simi'lar to Fig. 4 but showing1 the hammer in the rearmost position; an

Patented Nov. 23, ioeo.

v 1 1g. 6 1s a vertical section vlewed 1n the opposite direction from that of Fig. 2 (via. from the muzzle end of the gun) showing a detail hereinafter referred t i Fig. 7 is a section taken approximately on the line 7- of Fig. 2, and I F 8 is a section taken approximately on the line 8-8 of Fig. 2. I

A (Fig. l) is the carrier, B the box slide, and G the axial vent bolt to which the box slide is connected by a continuous screw thread or by interrupted collars inthe usual manner. D is the lock frame movable in an upward direction on the box slide to expose the primer chamber' in the axial vent bolt, D is a lock frame operating handle pivoted at d" to a bracket D attached to the lock frame, and 07 (F ig. 6) is a hookshaped projection on the handle D for engaging in a recess 6' in the box slide to hold the lock frame in the closed position. E is the firing hammer pivoted at e to the lock frame so as to move in a plane at right angles I to the path of travel of the lock frame, and E is a projection on the hammer E, this projection having an inclined surface with which an extension D of the handle D engages to slightly retract the hammer when the handle is rocked about its pivot-to di sngage the projection 03' from its recess b prior to the movement of the lock frame to the open position, this retraction of the hammer being for the purpose of bringing its striking point clear of the box slide during the movement of the lock frame.

E is the firing spring and e is its plunger engaging with projections e", 6' one on each side of the hammer pivot e; The lock frame D is formed with longitudinal grooves adapted to engage with fins B B onthe box slide B and also with fins 0 C on the axial vent f When the hammer is moved rearward, the forward projection e" on the hammer displaces the plunger 6 to energize the spring E (see ig. 5) and when the hammer is then released, it flies forward under the in fiuence of the spring acting on the projection a, the momentum of the hammer carrying it past the position shown by Fig. i to bring the rear projection e against the spring plunger; the subsequent reaction of the spring operating upon the hammer through the projection e then causes the hammer to be slightly retracted into the position of equilibrium shown by Fig. 4.

A projection E extending to the rear of the hammer serves to receive the lanyard hook which is retained in position by means of a lanyard guard 12" disposed in the hammer and mounted on the pivot pin 6 of the hammer. The lanyard uard is moved into the position shown by Big. 5 by the contact of a face 6 on the guard with a stop 5X or the lock frame, thereby freeing the lanyard the receiver or box slide in which the lockand releasing the hammer; this arrangement constituting firing mechanism of the sliplock hammer type. The rearward movement of the hammer is limited by a step c" and the hammer may have a projection E (Fig. 5) for the purpose of holding the hammer in the retracted position while the lock is sliding in the box slide. hen the lock frame is arranged to move at an in clination as shown by Fig.1, a fairlead E is provided for the lanyard so that the inner portion of the lanyard lies at therequircd anglIe.

hat we claim and desire to secure by Letters Patent of the United States 1. In ordnance lock mechanism, the combination with the wedge or lock frame and frame moves, ofa firing mechanism of the slip-lock hammer type, the hammer beings: pivoted to said lock frame so as to moveie a plane transverse to the path of travel of the lock frame, an operating handle for the lock frame and means whereby movement of said handle preparatoryto displacing the lock frame to the open position causesfthe hammer to be retracted.

2. In ordnance. lock mechanism, the combination with the wedge or lock frame and the receiver or box slide in which the lock frame moves, of a firing hammer pivoted bination with the wedge or look frame and the receiver or box slidein which the lock frame moves, of a firing hammer pivoted to said lock frame so as to move in a plane transverse to the path of travel of the lock frame and a spring adapted to operate upon the hammer to one side or the other of its pivot according to the position of the hammer.

4. In ordnance lock mechanism, the combination with the wedge or look frame and the receiver or box slide in which the lock frame moves, of a firing hammer pivoted to said lock frame so as to move in a plane transverse to the path of travel of the lock frame and provided with projections one on each side of the pivotal axis of the ham-- mer and a spring plunger with which one or the other or both of said projections are adapted to engage according to the position of the hammer, the hammer being in a retracted position of equilibrium when both the projections are engaging with the plun er.

5. n ordnance lock mechanism, the combination with the wedge or lock frame and the receiver or box slide in which the lock frame moves, of a firing hammer pivoted to said lock frame so as to move in a plane transverse to the path of travel of the lock frame and provided with projections one on each side of thepivotal axis of the hammer, a firing spring for said hammer and a plunger subjectto the influence of said spring with which plunger one or the other or both of said projections are adapted to engage according to the position of the hammer, the hammer'being in a retracted position of equilibrium whenboth the projections are engaging with the plunger.

6. In ordnance lock mechanism, the com bination with the wedge or look frame and the receiver or box slide in which the lock frame moves, of firing mechanism of the slip-lock hammer type, the hammer being pivoted to said lock frame so to move in a plane transverse to the path of travel of the lock frame, an operating handle on the lock frame and means whereby movement of said handle preparatory to displacing the lock frame to the open position causes the hammer to be retracted. v

r 7. In ordnance lock mechanism, the comhinationwith the wedge or look frame and the receiver or box slide in which the lock frame moves, of firing mechanism' of the slip-lock hammer type the hammer being pivoted to said lock frame so as to move in a plane transverse to the path'of travel of the lock frame and a spring adapted to operate upon thehammer to one side or the other of its pivot according to the position of the hammer.

In testimony whereof we aflix' our signatures. 

